SRA

Phylogeny of the Australian Solanum dioicum group using seven nuclear genes: testing Symon's fruit and seed dispersal hypotheses .The dioecious and andromonoecious Solanum taxa (previously described as the “S. dioicum group”) of the Australian Monsoon Tropics (AMT) have been the subject of phylogenetic and taxonomic study for the last 20 years, yet much of their basic biology is still unknown. This is especially true for plant-animal interactions, including the influence of fruit form and calyx morphology on seed dispersal. We combine field/greenhouse observations and specimen-based study with phylogenetic hypotheses from seven nuclear regions obtained via the Fluidigm access array sequenced with Illumina and present the first intron-containing nuclear gene dataset in the genus Solanum and the first species-tree hypothesis for the S. dioicum group. Our results suggest that epizoochorous trample-burr seed dispersal (strongly linked to calyx accrescence) is far more common among Australian Solanum than previously thought and support the hypothesis that large fleshy fruits and endozoochorous dispersal are derived conditions in this study group. The general lack of direct evidence related to biotic dispersal (epizoochorous endozoochorous or endozoochorous epizoochorous ) may be a function of declines and/or extinctions of mammalian dispersers. Because of this, some taxa might now rely on secondary dispersal mechanisms (e.g. shakers, tumbleweeds, rafting) as a means to maintain current populations and establish new ones.